Heretofore, a filter apparatus has been known for removing dust, particulates and the like contained within a pressure fluid that is supplied to fluid pressure devices. For example, as disclosed in Japanese Laid-Open Patent Publication No. 2008-188489, such a filter apparatus is constituted from a fluid inlet port provided on an upstream side of a fluid pressure device supplied with the pressure fluid, and to which the pressure fluid is supplied, a main body having a fluid outlet port through which the pressure fluid is discharged, a filter element connected to a lower portion of the main body, and a case, which is connected to a lower portion of the main body so as to cover the filter element.
In addition, the pressure fluid, which is supplied to the fluid inlet port, is introduced to the interior of the case and passes from an outer circumferential side to an inner circumferential side of the filter element, whereby dust, particulates and the like contained within the pressure fluid are removed. A clean pressure fluid flows to the fluid outlet port from the inner circumferential side of the filter element, and thereafter the clean pressure fluid is supplied to other downstream fluid pressure devices.